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Author Spotlight: Real-Time Monitoring of Parasite Burden and Host Response
Published on: May 31, 2024
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On-off intermittency and irruptions in host-parasitoid dynamics
Gabriele Vissio1, Antonello Provenzale2
1Institute of Geosciences and Earth Resources (IGG) - National Research Council (CNR), Via Valperga Caluso 35, 10125 Turin, Italy.
Journal of Theoretical Biology
|June 1, 2022
Summary
Environmental changes can cause population outbreaks. This study shows how random fluctuations in host-parasitoid systems lead to on-off intermittency, mimicking sudden population bursts and ecosystem instability.
Area of Science:
- Ecology
- Mathematical Biology
- Population Dynamics
Background:
- Environmental stochasticity significantly impacts ecosystem stability and population dynamics.
- Host-parasitoid interactions are crucial components of ecological systems, influencing population fluctuations.
- Previous models often simplify environmental variability, potentially missing key dynamic behaviors.
Purpose of the Study:
- To investigate the effects of environmental stochasticity on coupled host-parasitoid dynamics.
- To analyze how parameter perturbations in host or host-parasitoid interactions alter system stability.
- To identify and describe emergent dynamic behaviors, such as population outbreaks, under stochastic conditions.
Main Methods:
- Utilized Beddington's conceptual two-dimensional map for host-parasitoid dynamics.
- Introduced stochastic perturbations to key parameters governing host dynamics and host-parasitoid interactions.
- Analyzed the resulting system dynamics for characteristic patterns and transitions.
Main Results:
- Stochastic perturbations induced a dramatic shift in system dynamics.
- Observed the emergence of on-off intermittency, characterized by alternating quiescent periods and population bursts.
- Demonstrated that these bursts represent a qualitative, environmentally driven mechanism for population outbreaks.
Conclusions:
- Environmental stochasticity can destabilize host-parasitoid systems, leading to unpredictable population dynamics.
- On-off intermittency provides a novel framework for understanding the environmental basis of population outbreaks.
- The study highlights the importance of incorporating environmental variability into ecological models to accurately predict population dynamics.
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